Serial release mechanism and drainage monitor embodying the same

ABSTRACT

A serial release mechanism, a serial release method, and a discharge monitor including the mechanism, which mechanism includes first and subsequent actuators slidable in a frame between working and withdrawn positions, springs urging the subsequent actuators into their working positions, latch tabs carried by the subsequent actuators and triggers resiliently pivoted to the frame for releasably retaining the subsequent actuators in their withdrawn positions, a shaft of noncircular cross section and a plurality of saddles for releasing the triggers of the subsequent actuators and having operating fingers and being rotatable with the shaft and slidable therealong between first positions in which they are aligned with the triggers and second positions in which they are not so aligned, saddle springs resiliently urging the saddles along the shaft into their second positions, and shifter springs carried by the actuators and the frame, and effective when any actuator is in working position to displace the succeeding saddle into its first position, so that subsequent rotation of the shaft causes the finger to release the trigger.

This is a division of application Ser. No. 847,701, filed Nov. 2, 1977now U.S. Pat. No. 4,181,121.

BACKGROUND OF THE INVENTION

This invention relates to the field of medicine, and particularly toapparatus whereby medical personnel may collect and keep reliablerecords of the liquid output of a patient. The equipment is speciallydesigned for monitoring the volumetric urine output of a patient atregularly hourly intervals, for a total period longer than the usualwork shift of hospital personnel.

The importance of knowledge of the patient's renal output is well knownin medicine. A knowledge of the volumes of urine excreted by a patientover particular periods of time is extremely helpful in the managementof fluid imbalances or electrolyte abnormalities. In cases where thepatient has been in shock and the renal function is questionable, as insevere burn cases, urine output measurement is very important. Also, invirtually any serious illness, injury or operational procedure where areduction in blood volume is anticipated, accurate measurement of smallurinary volume output is either mandatory or highly desirable.

Accurate urine measurement are an aid in recognizing the onset ofimpending post-surgical shock. For this reason, the urine volumes ofmany post-surgical patients are measured hourly, particularly those whohave undergone cardiac, thoracic, neurological or genitourinary surgery.

SUMMARY OF THE INVENTION

Numerous structures are known for monitoring the renal output of thepatient, from a simple graduated cylinder at the end of an indwellingcatheter to a highly mechanized arrangement such as that of Scott U.S.Pat. No. 3,194,069, for example. Our invention comprises an improvementon the structure shown in the copending patent application of one of us,Ser. No. 847,249, filed Oct. 31, 1977, now U.S. Pat. No. 4,206,767,issued June 10, 1980, and assigned to the assignee of the presentapplication.

In the copending application there is disclosed a monitoring arrangementwhich has the advantages of completely unsupervised operation tocollect, in sequential chambers, the excretions for ten successivehours, in a form resembling a bar graph or histogram for convenientobservation in this closed or sealed system adapted either for emptyingand resterilizing or preferably for disposable use, the manipulations atthe end of the total collecting period to prepare for a second selectionperiod an simple, convenient, and sanitary.

Our improvement, described and claimed herein, replaces the rathercomplex computer control of liquid flow of the earlier structure by arelatively simple serial release mechanism which eliminates theelectronic counter, multivibrators, amplifiers, and multiple solenoidsof the previous structure while performing the same functions. A timerenergizes a single solenoid at predetermined intervals, and thediversion of liquid flow to the sequential chambers is all accomplishedmechanically. This results in long periods of trouble free operation ofthe equipment, a special advantage in hospital use.

Various other advantages and features of novelty which characterize ourinvention are pointed out with particularity in the claims annexedhereto and forming a part hereof. However, for a better understanding ofthe invention, its advantages, and objects attained by its use,reference should be had to the drawing which forms a further parthereof, and to accompanying descriptive matter, in which there isillustrated and described a preferred embodiment of the invention.

BRIEF DESCRIPTION OF THE DRAWING

In the drawing, FIG. 1 is a view in elevation of a drainage monitorembodying our invention;

FIGS. 2 and 3 are fragmentary sectional views taken along the lines 2--2and 3--3 of FIG. 1;

FIG. 4 shows a detail;

FIG. 5 is a plan view of our serial release mechanism, seen generallyfrom the line 5--5 of FIG. 1; parts being shown in section;

FIG. 6 is a sectional view generally along the line 6--6 of FIG. 5;

FIG. 7a and 7b are sectional views along the lines 7--7 in FIG. 5showing different conditions of the apparatus;

FIG. 8 is a sectional view along the line 8--8 of FIG. 5;

FIG. 9 is a fragmentary rear view, seen from 9--9 of FIG. 5;

FIG. 10 is an exploded view of the elements of a subassembly used in theinvention; and

FIG. 11 is an electrical schematic.

DESCRIPTION OF THE PREFERRED EMBODIMENT

A drainage monitor 20 embodying our invention is shown in FIGS. 1-3 tocomprise a liquid collector 21 and a control unit 22 having a handle 19.Collector 21 comprises a storage section 23 and a manifold section 24.Storage section 23 includes a row of chambers 25, 26, 27, 28, 30, 31,32, 33, 34 and 35 into which liquid is to be delivered serially,beginning with chamber 25. The chambers are interconnected at theirtops, as indicated at 36, and the interconnection is extended to anoverflow connection 37 having a pinch clamp 38. Manifold section 24includes an inlet 39, a drip chamber 40, and a header 41 having aplurality of taps 42 equal in number to the number of chambers. Thesections are physically interconnected by a bridging member 43 havingupper and lower flanges 44 and 45 sealed thereto as at 46 and 47, andincluding a central reaction bar 50 strengthened by longitudinal ribs 51and 52 and formed with apertures 53 centrally and near its ends to passtoggle bolts 54 projecting outward from the front 55 of control unit 22.Liquid may pass from section 24 to section 23 through a plurality ofcollapsible flexible tubes 56 secured to taps 42 and the tops ofchambers 25-35 inclusive. This arrangement is fully described in thecopending application referred to above.

As shown in FIG. 3, flow of liquid from header 41 to each of thechambers, such as chamber 32, may be interrupted by means described morefully below, which compresses tube 56 against reaction bar 50,completely collapsing the tube so that no opening remains for passage ofliquid therethrough. The normal state of tube 56 is shown in FIG. 3 infull lines, and its collapsed or occluded state in broken lines. Liquidfrom input 39 flows into chamber 25 until cut off, then into chamber 26,and so on. The serial release mechanism by which occlusion of tubes 56in a desired order at predetermined times is accomplished will now bedescribed.

As shown in FIGS. 5-10, serial release mechanism 57 comprises a frame 58having a front wall 59 and a rear wall 60 and mounting a solenoid 61,which acts through a shaft 62 having a flat 63 to cause sequentialoperation of release sub-assemblies one less in number than the numberof chambers 25-35: thus, subassembly 65 cooperates with the tube 56leading to chamber 25, subassembly 72 with the tubes 56 leading tochamber 32, and so on. No sub-assembly is needed for the tube 56 leadingto chamber 35, the final chamber in the series. The sub-assemblies aremounted on frame 58 and are suitably spaced in agreement with thespacing between the tubes 56 of a collector positioned on toggle bolts54.

Shaft 62 is supported by a plurality of brackets 75 secured to frame 58and having spaced left and right arms 76 and 77 with aligned apertures78 and 79 to act as bearings for the shaft. In order to perform itsfunction shaft 62 is noncircular, flat 63 extending its full length, butthe depth of a flat is not enough to interfere with the bearing supportoffered by round apertures 78 and 79. The spacing between arms 76 and 77of each bracket, and the spacings between the brackets, are such thateach of sub-assemblies 65-74 is in operative coaction with an arm of abracket.

As shown most clearly in exploded view 10, each sub-assembly comprisesan actuator 80, an actuator spring 81, a trigger 82, a trigger spring83, a release saddle 85, a saddle spring 86 (omitted in sub-assembly 65)and a shifter spring 87, all operationally interrelated as will now bedescribed. Actuator 80 slides in frame 58 between working and withdrawnpositions: it comprises a flat blade having a tongue 90 at one end and atail 91 at the other end, and carries a latch tab 92. Frame 58 isprovided with a plurality of front slots 93 to pass the tongues 90, anda plurality of rear slots 94 to pass the tails 91, of the actuators.Spring 81 functions to normally urge actuator 80 outward into itsworking position. To insert an actuator in the frame, a spring 81 isplaced over tail 91 and the latter is positioned in line with the insideof a slot 94. The spring is compressed between tab 92 and rear wall 60,allowing tail 91 to move out through slot 94 until tongue 90 comeswithin the front wall 59 and can be aligned with slot 93: release ofcompression force allows spring 81 to move tongue 90 outwardly until tab92 engages the inner surface of wall 59.

Trigger means are provided to releasably retain the actuators in thewithdrawn positions. For this purpose latch tab 92 has a slot 95 sizedto receive the front end 96 of trigger 82. The rear end 97 of trigger 82passes through an aperture 100 in rear wall 60 and is upwardly notchedat 101 to engage that wall: it is downwardly shouldered at 102 to engageend 103 of spring 83. The other end 104 of the spring is bent to engagethe inner surface of wall 60, and then to pass through apertures 100,thus, securing the trigger in the opening. Springs 83 function to urgetriggers 82 forwardly and downwardly, so that if pressure is appliedinwardly to tongue 90, compressing spring 81, tab 92 slides rearwardlyuntil it reaches a detent shoulder 105 formed in trigger 82, whereuponthe trigger drops under the influence spring 83, holding actuator 80 outof its working position and in a withdrawn position.

Saddles 85 are provided to release triggers 82 and so allow actuators 80to move from the withdrawn positions. Each saddle has legs 106 and 107with aligned apertures 110 and 111 to receive shaft 62, one of thembeing noncircular so that the saddles rotate with the shaft, but mayslide therealong. Leg 107 is formed with an operating finger 112extending outwardly parallel to the axis 113 of shaft 62. As bestindicated in FIG. 10, shaft 62 passes through aperture 111 of leg 107,then through arm 77 of bracket 75, then through spring 86, then throughaperture 110 of leg 106, and so forth. By this arrangement spring 86urges saddle 85 to the left on shaft 82 until the inner surface of leg107 engages the outer surface of arm 77. In this position, as is shownin FIG. 3, finger 112 does not extend under a central portion 114 oftrigger 82, and clockwise rotation of shaft 62, while it rotates saddle85 and finger 112 does not affect the trigger. Spring 86 thus disablesthe release function of the saddle 85 and shaft 62.

It is the function of shifter spring 87 to override the disablingfunction by displacing saddle 85 to the right, against the force ofweaker spring 86, until finger 112 projects beneath trigger surface 114.Each tab 92 has an aperture 115 in its face and a notch 116 in its edge,and rear wall 60 has a plurality of apertures 117, for coaction withspring 87. One end 120 of the latter is formed with a 90° bend 121received in apertures 115: it is held in slot 116 by a U-shaped bend122, and is provided with a further bend 123 at an obtuse angle afterwhich the other end 124 passes through apertures 117. As best shown insub-assembly 73, FIG. 5, when actuator 90 is withdrawn, the portion 125of spring 87 between bends 122 and 123 extends transversely across theframe, beside leg 106 of saddle 85 are displaced by spring 86, but notbearing significantly against it. Finger 112 is withdrawn from beneathtrigger 82. However, when the actuator is in its working position, withtongue 90 extended, as in sub-assembly 72, the contact of end 124 ofspring 87 with aperture 117 forces bend 123 of the spring to the right,against leg 106 of the saddle, compressing spring 86 and displacing thesaddle so that the finger 112 contacts the face of trigger 82; when theshaft is released the finger passes beneath trigger 82. Rotation ofshaft 62 may now lift the trigger until detent 105 clears the bottom ofslot 95, and that spring 81 may move actuator 80 into its workingposition. Surface 126 of trigger 82 now rides on the bottom of slot 95,holding surface 114 above finger 112 to remove any load on finger 112from spring 83 in this sub-assembly.

Referring to FIGS. 5 and 6, saddle 85 of subassembly 64 is not providedwith a spring 86, but is secured against axial movement on shaft 62 by acollar 127 and set screw 130.

Turning now to FIG. 8, solenoid 61 is mounted on an extension 131 ofrear wall 60 by suitable fasteners 132: the electrical terminals of thesolenoid are showed at 133, and its plunger 134 is urged outwardly byspring 135. An actuating arm 136 is secured to shaft 62 by a set screw137, and is slotted at 140 to receive a pin 141 at the end of plugger134. Arm 136 is formed with projecting stop surfaces 142 and 143 tolimit the movement of shaft 62 in each direction, slide adjustment beingmade possible by the provision of slots 144, 145.

A signalling miniature switch 146 may be mounted on a suitable bracket147 for actuation by tab 92 of subassembly 74, if desired.

FIG. 11 shows the extremely simply electrical circuitry needed for thisserial release mechanism. A timer 150 of any suitable electrical ormechanical type supplies brief electrical signals at predeterminedintervals from any suitable source, here shown as a battery 151, tosolenoid 61, on conductors 152, 153 and 154: each signal causesenergization of the solenoid, and results in operation of the mechanismas will now be described.

OPERATION

The operation of a drainage monitor embodying our improved serialrelease mechanism will now be readily understood. A control unit havingan adequate source of electrical energy is carried to the site of useand secured to a suitable support. Actuators 80 are displaced inwardlyby manual pressure on tongues 90 until tabs 92 pass behind detents 105of triggers 82, and the triggers drop, under the impulses of springs 83,to retain the actuators in withdrawn positions. Toggle bolts 54 aremoved to their FIG. 4 positions, and a collector 21 is positioned sothat apertures 53 in bar 50 pass over the toggle bolts, which are thenmoved to their FIG. 3 positions to maintain the collector in place. Inthis state of the equipment each tube 56 is in line with an actuatortongue 90, and its side away from the actuator is close to or in contactwith bar 50. The discharge end of an indwelling catheter or other liquidsource is connected to inlet 39, and operation of timer 150 isinitiated. Liquid discharge drops through chamber 40, the first tap 42,and the first tube 56 into the first, left hand chamber 25 of storagesection 23, where its quantity, color, and so forth can be visuallyobserved.

At the end of one hour timer 150 supplies a short pulse to solenoid 61,which rotates shaft 62 and saddles 85 in a counterclockwise direction asseen in FIG. 8. Finger 112 of the first saddle is always beneath trigger82, but the fingers of all the other saddles are displaced by theirsprings 86 to clear the respective triggers, as shown in FIG. 5 withrespect to subassembly 74. Rotation of shaft 62 thus acts through saddle85 and finger 112 of subassembly 65 only, to raise the trigger andrelease the actuator, the tongue 90 of which presses tube 56 against bar50 so strongly as to close the tube. No more liquid may pass intochamber 25, but liquid continues to drop until the header tap at chamber25 is filled, and then flows along header 24 to the next tap, in series,and so into chamber 26.

When the energization of solenoid 61 ceases, its plunger is withdrawn,and shaft 62 is returned to its initial position, by springs 135. Frontportion 126 of trigger 82 now rests on the bottom of slot 95, andsurface 114 of the trigger remains above the highest position of finger112, although the latter remains beneath the trigger. Succeedingoperations of solenoid 61 are thus ineffective against the trigger ofany sub-assembly for which the actuator is in working position.

Movement of actuator 80 of sub-assembly 65 has moved spring 87 inaperture 117 so that bend 123 presses against leg 106 of the saddle 85for the next sub-assembly, displacing saddle 85 by overcoming the forceof spring 86 so that its finger 112 moves beneath its trigger. This isas shown in FIG. 5 for sub-assemblies 72 and 73. The next energizationof solenoid 61 is to release the actuator of the sub-assembly next tosub-assembly 65, and so on.

Attention should now be directed to the relation between sub-assembly72, 73 and 74, which clearly illustrate how the serial release of theactuators take place. Finger 112 in sub-assembly 74 is displaced to theleft from beneath trigger 82, by spring 86. Finger 112 in sub-assembly72 is beneath trigger 82, but the latter has released actuator 80 and israised by slot 95 out of reach of finger 112. Bend 123 of spring 87 isin engagement with leg 106 of saddle 85, overcoming the force of spring86 and displacing the saddle, and with it finger 112, to the right sothat the finger is beneath trigger 82. The next operation of shaft 62will therefore be ineffective in sub-assembly 72, and all previoussub-assemblies in the series, and will be ineffective in sub-assembly74, but will raise trigger 82 of sub-assembly 73, to release itsactuator. FIG. 7a shows sub-assembly 73 with its actuator withdrawn, andFIG. 7b shows the same sub-assembly just after the finger 112 hasreleased trigger 82, which has been raised, by contact with the bottomof the slot in tab 92, out of engagement with finger 112 even whilesaddle 85 still remains rotated.

The foregoing explanation makes it clear that the mechanism operatesupon each solenoid operation to release one actuator, the next in theseries, whereby to cut off the flow of liquids to the successivechambers in turn. For other applications of the mechanism, it may bedesired to release more than one actuator at a time. To release theactuators in threes, for example, it is only necessary to refrain frompressing in the actuator tongues for the first, fourth, and seventhsub-assemblies. These actuators only will then be in working positionsinitially, the fingers of the second, fifth and eight sub-assemblieswill be positioned beneath their respective triggers, and those in thethird, sixth, and ninth sub-assemblies will not be so positioned. Thenext solenoid energization will accordingly release the triggers of thesecond, fifth and eight actuators simultaneously, and so on. The sameresult may be even more neatly accomplished by substituting axiallyfixed saddles, such as that shown for sub-assembly 65, at the fourth andseventh sub-assemblies as well: by this expedient all nine of thesub-assemblies may have two positions.

Of course, a greater or lesser number of actuators may be used, bylengthening or shortening shaft 62, as the needs of particular specialapplications may dictate, and may be arranged for dual or multiplesimultaneous operations rather than single operation, as may be desired.

From the foregoing it will be evident that we have invented a new andimproved serial release mechanism and an improved discharge monitor inwhich the mechanism is particularly useful, although it will be ofgeneral utility wherever serial operation of single actuators oractuatores in pairs or sets is desired.

Numerous characteristics and advantages of our invention have been setforth in the foregoing description, together with details of thestructure and function of the invention, and the novel features thereofare pointed out in the appended claims. The disclosure, however, isillustrative only, and changes may be made in detail, especially inmatters of shape, size, and arrangement of parts, within the principleof the invention, to the full extent indicated by the broad generalmeaning of the terms in which the appended claims are expressed.

What is claimed is:
 1. In a serial release mechanism, incombination:series of actuators normally urged resiliently into first,working positions; trigger means releasably holding said actuators insecond, withdrawn positions; trigger release means effective in a firststate, when operated, to release said trigger means; means for operatingsaid trigger release means; disabling means normally effective toactuate said trigger release means into a second state in which releaseof said trigger means thereby is prevented; and override meanseffective, when any actuator in a series is in working position, tooverride the release disablement of only the next actuator in theseries, so that successive operations of the operating means causesuccessive release of single actuators in said series.
 2. A structureaccording to claim 1 in which there is a single series of actuators andsuccessive operation of the operating means causes successive release ofsaid actuators singly in series.
 3. A structure according to claim 1 inwhich there are plural series of actuators, and successive operations ofsaid trigger release means cause successive simultaneous release ofsingle actuators in each said series.
 4. Apparatus according to claim 3which includes separate trigger means, trigger release means, disablingmeans, and override means for each of said actuators, and in which saidtrigger release means are simultaneously operable.
 5. Apparatusaccording to claim 4 in which said trigger release means aresimultaneously rotatable an individually movable axially, and in whichsaid disabling means displace said release means axially out ofoperative first positions and into inoperative second positions.
 6. In aserial release mechanism, in combination:a frame; first and secondactuators slidable in said frame between working and withdrawnpositions; resilient means urging said second actuator into said workingposition; trigger means, including a latch tab carried by said secondactuator and a trigger resiliently pivoted to said frame, for releasablyretaining said second actuator in said withdrawn position; triggerrelease means including a shaft of noncircular cross section and asaddle having an operating finger, said saddle being rotatable with saidshaft and slidable therealong between a first position, in which saidfinger is aligned with said trigger, and a second position, in whichsaid finger is not aligned with said trigger; disabling means, includinga saddle spring, resiliently urging said saddle along said shaft intosaid second position, so that rotation of said shaft does not causerelease of said trigger; means for displacing said first actuator intoits working position; and override means including a shifter springcarried by said first actuator and said frame, and effective when saidfirst actuator is in working position to displace said saddle into saidfirst position, so that subsequent rotation of said shaft causes saidfinger to release said trigger.
 7. In a serial release mechanism, incombination:a frame; first and subsequent actuators slidable in saidframe between working and withdrawn positions; resilient means urgingsaid subsequent actuators into said working positions; trigger means,including latch tabs carried by said subsequent actuators and triggersresiliently pivoted to said frame, for releasably retaining saidsubsequent actuators in said withdrawn positions; trigger release meansincluding a shaft of noncircular cross section and a plurality ofsaddles for releasing the triggers of said subsequent actuators, saidsaddles having operating fingers and being rotated with said shaft andslidable therealong between first positions, in which they are alignedwith said triggers, and second positions, in which they are not alignedwith said triggers; disabling means, including saddle springs,resiliently urging said saddles along said shaft into said secondpositions, so that rotation of said shaft does not cause release of saidtriggers; means for displacing said first actuator into its workingposition; and override means including shifter springs carried by saidactuators and said frame, and effective when any actuator is in workingposition to displace the succeeding saddle into its first position, sothat subsequent rotation of said shaft causes said finger to releasesaid trigger.
 8. In a serial release mechanism, in combination:a frame;an actuator slidable in said frame between working and withdrawnpositions; resilient means urging said actuator into said workingposition; trigger means, including a latch tab carried by said actuatorand a trigger resiliently pivoted to said frame, for releasablyretaining said actuator in said withdrawn position; trigger releasemeans including a shaft of noncircular section and a saddle having anoperating finger, said saddle being rotatable with said shaft andslidable therealong between a first position, in which said finger isaligned with said trigger, and a second position, in which said fingeris not aligned with said trigger; disabling means including a saddlespring urging said saddle along said shaft to said second position; andoverride means including a shifter spring effective to displace saidsaddle against said saddle spring into said first position thereof, sothat rotation of said shaft causes said finger to release said trigger.9. In a serial release mechanism, in combination:an elongated framehaving a low front wall and a higher rear wall; bracket means secured tosaid frame between said walls to provide a plurality of upwardlydirected spaced arms having longitudinally aligned circular bearingapertures; a shaft carried in said apertures and having a flat extendingtherealong to give the shaft a noncircular cross section; meansresiliently retaining said shaft in a normal angular position; powermeans actuable to cause repeated angular displacement of said shaftthrough the same predetermined acute angle; a plurality of spacedaligned actuators positioned in serial adjacency along said frame andhaving forward tongues, rearward tails, and upwardly projectingtransverse latch tabs; aligned slots in the lower portions of said frontand rear walls, to slidingly receive said tongues and said tailsrespectively of said actuators; first compression spring means carriedby said actuators, and engaging the inner surface of said rear wall, forurging said actuators into working positions in which said tonguesproject through and beyond said front wall and said tabs engage theinner surface of said front wall; slots in said latch tabs; triggersreceived in said slots and pivoted in said rear wall; resilient meansacting between said rear wall and said triggers to cause the latter toride on the bottoms of said slots as said actuators slide inwardly fromsaid working position; detents in said triggers to engage said latchtabs when said actuators are in said withdrawn positions and retain theactuators in said withdrawn positions; saddles, having operatingfingers, rotatable with said shaft and slidable therealong between firstpositions, in which said fingers extend beneath said triggers, andsecond positions, in which said triggers are withdrawn from beneath saidtriggers; saddle springs carried on said shaft and acting between saidsaddles and said arms of said bracket means to resiliently urge saidsaddles into said second positions; means for releasing the trigger ofthe first of said actuators; shifter springs carried by each of saidactuators and by said rear wall, and configured so that when anyactuator is in the withdrawn position, the shifter spring is withouteffect upon the saddle of the adjacent actuator, and so that when anyactuator is in working position said shifter spring displaces the saddleof the adjacent actuator into the first position thereof, all wherebyafter the trigger of said first actuator is released, successiveactuations of said power means enables serial release of said actuatorssingly into their working positions.